Where must automatic methane detectors be located on or near a long wall face?

• A. Longwall Shearer
• B. The intersection between the longwall face and an intake airway
• C. AFC TG drive
• D. All of the above

Answer: (D)

Early detection of methane at multiple high‑risk points along the longwall is essential for safe ventilation management. Placing automatic methane detectors on or near the longwall face ensures any methane released during cutting or from the face area is detected promptly, so ventilation can be adjusted and alarms triggered to protect workers.

The intersection between the longwall face and the intake airway is another critical location. Gas can migrate from the face into the intake air as the face advances, creating pockets where methane concentration may rise. Detectors at this junction provide early warning before methane is drawn deeper into the intake system and reaches other occupied areas.

Equipment areas such as the AFC drive and the TG drive are also high‑risk zones. Machinery and belt conveyors can release or trap methane, and the confined spaces around these drives can accumulate gas quickly. Detectors there give timely alerts to shut down or reconfigure ventilation and prevent hazardous conditions.

Since all these spots pose methane risks, placing detectors in each location ensures comprehensive coverage and rapid response, which is why all of the above locations are required.